map.js

/* global jsonld */

'use strict'

var iframeTemplate = '<iframe src="https://map.geo.admin.ch/embed.html?${mapId}" style="width:100%; height: 300px; border: 0;"></iframe>'
var geoJsonLinkTemplate = '<a class="pull-right" href="${geoJsonUrl}" target="_blank">Download as GeoJSON</a>'

function addMapIFrame (subject) {
  var html = ''

  if ('http://schema.org/hasMap' in subject) {
    var mapUrl = subject['http://schema.org/hasMap'][0]['@id']
    var embeddedUrl = mapUrl.split('?').pop()

    html += iframeTemplate.replace('${mapId}', embeddedUrl)
  }

  if ('http://schema.org/sameAs' in subject) {
    html += geoJsonLinkTemplate.replace('${geoJsonUrl}', subject['http://schema.org/sameAs'][0]['@id'])
  }

  var element = document.getElementById('map')

  element.innerHTML = html
}

function embeddedJsonLd () {
  var element = document.getElementById('data')

  if (!element) {
    return Promise.reject()
  }

  var json = JSON.parse(element.innerHTML)

  return jsonld.promises.flatten(json, {}).then(function (flat) {
    return jsonld.promises.expand(flat)
  })
}

embeddedJsonLd().then(function (graph) {
  var subjectUrl = document.createElement('a')
  var windowUrl = document.createElement('a')
  windowUrl.href = window.location.href

  var subject = graph.filter(function (subject) {
    subjectUrl.href = subject['@id']

    return subjectUrl.pathname === windowUrl.pathname
  }).shift()

  if (subject) {
    addMapIFrame(subject)
  }
}).catch(function (err) {
  console.error(err)
})